Identification and characterization of the types of synapses that occur on the spatially and electrotonically distant terminals of modulatory projection neurons from their neural network targets, as well as the functional consequences of these presynaptic inputs for neural network activity are the focus of this study. The work is performed in the stomatogastric nervous system of the crab, Cancer borealis. For confocal microscopy, we are using neurobiotin dye-fills to identify dye-coupling, and consequently electrical coupling, between the terminals of these projection neurons and individual, identified neural network components. 8-31-96